High speed printer



y 7, 1959 a. H. PEKAR EIAL 2,893,313

' HIGH SPEED PRINTER Filed March 17, 1958 x. t 4/ I 7 4a 47 INVENTORS GEORGE H. PEKAR ARTHUR s. 0 son I BY I M ATTORNEYS United States Patent HIGH SPEED PRINTER *George H. 'Pekar, Arlington, and Arthur S.'0sborn, Falls Church, Va., assignors to the United States of America as represented by the Secretary of the .Air Force Application March 17, 1958,Serial'No.722;105

7 Claims. "(Cl..101-93) "Thisinvention rel-ates generally to an ultrahigh speed percussion imprint 'printer, or "converter, which will record selected type characters or symbolic figures, when connected through proper circuitry, to high speed 'com- 'puter outputs. More particularly, the invention is con- *cernedwith a simply constructed mechanism capable of providing "an accurately aligned printed record of the rapidly flowing data froma computing machine.

The increasing use of high speed computers to solve various scientific and business problems, raised the "problem of quickly and accurately presenting the data 'gathered by these computers. Since a considerable amount of data is presented in a'very :short space oftime, .it becomes necessary to provide a means whereby this data *can be removed from storage and rapidly recorded. An accepted method of recording this data is "by the use of a high speed printer in, which the print wheels carrying *theft-ype rotate continuously and are struck at the proper instant by hammers or platens which drive "the record ing medium against selected characters on 'the rotating "typeywheels. This technique of printinghis generally known as printing *on the fly and is particularly adapted for use where rapid operation is essential.

The-present invention is a modification :o'f 'thegabove described type of high speed printer. Instead (if-a solemoid or some other electromagnetic device operatingidb rectly or through linkage to cause the hammer 'or platen toforce the recording medium against a typewhe'el, the present invention utilizes a novel mechanical system'which includes a rotating-cam member and an insertable spacer to' drive the platen and printing medium against the *typewheel. The useof mechanical "rather than 'electrornagn'etic means as the source of the striking force to produce the imprint results in a printed record which is anorenearly in accurate horizontal line alignment. "Less precision in electrical input pulse timing is required to maintain horizontal alignment when using this mechanteal *system. H

Accordingly, a primary object of the present invention "is to provide a mechanism capable of rapidly and accurately recording on printed medium, the output "of a :high speed computer.

' .Anoth'er sbbje'ct of the invention is to provide-a simiplezmechanical system using .parts ofrminimum mass and unique configuration, thereby eliminating high inertia .aforces whic'hrare detrimental tohigh :speed'operation.

One of the particular advantages of the present l vention lies in the 'fact that even though the platen .is mechanically operated, the device is capable of responding to the rapid succession of output pulses characteristic of .high speed computers with accuracy, dependability and speed as great or greater than printers depending completely on electromagnetic means for actuating the platen. This is so with the additional advantage of less precision being required in input electrical timing synchronization. Also, the unique relationship between the spacer member and its actuating cam results in a mechanism which can operate at the necessary high speeds without jamming or misalignment.

These and other objects, features and advantages will become more apparent after considering the following detailed description taken in conjunction with the annexed drawings wherein:

Fig. .1 shows a diagrammatic view of the printing mechanism before receiving the actuating pulses from the computer;

Fig. 2 shows the mechanismimmediately after receiving the pulse; and

'Fig. '3 shows the cam lobe after striking the spacer which has in turn 'forced the platen and recording medium against the type wheel during the printing cycle.

Referring now to Fig. 1 there is shown a cross-sectional diagrammatic view of a single bank of the mechanism. It should 'be understood that any desired length chanical limitations, by adding additional'banks for each column 'of characters, or symbols, that is desired. 1n the embodiment shown a character wheel 13 having ten characters embossed thereon is mated in a predetermined angular relationship through gears 19 and .21 to the cam member 15 having five 'lobes. However, any number of characters and symbols may be added to the periphery of wheel 13 provided the necessary change 'in the number of lobes on the cam 15 is made so that the two wheels rotate according to a predetermined ratio.

Driving power is applied to the character wheel shaft 17 which in the embodiment shown is' coupled mechanically in a two to one ratio through the gears 19 and 21 to the cam shaft 23. This indexes each 'lobe on the cam member .15 with each character orsynibol on the character wheel '13.

The actual printing .cycle occurs during every other revolution of the character wheel 13 in order to allow for advancing the recording medium 25 during the intermediate cycles.

During the printing operation, the recording medium .25 is substantially stationary. Ihe cam member 15 and the characterwhee'l 13 rotate in the directions .of the arrows as shown .in-the figures. When a print pulse is received from -fl1e output of .a computer or some other system with an electrical output signal, the solenoid -27 is-energized, moving the lever 29, with the associated spacer '33, pivot37 and spring 45, about its pivotal and extending the lever return spring .32.

In Fig. 'l'and Fig. '2, the spacer 33 is depicted as in -a position of rest on a shoulder in the lower end of the lever '29. The spring 45 tends to rotate the spacer 33 the solenoid- .27. has been activated, moving rtheflever and extending the lever return spring 32 resulting in .the positioning of spacer '3'3 preparatory to contact by .the cam member '15. When thespacer 33 has been carried 'by the cam to thelocation dipictedin'FigJZ as rotation of the wheel 13 continues, a lobe of the cam 15 strikes the spacer 33. The force applied on the spacer 33 by a lobe of the cam 15, overcomes the return force of the spring 45, which causes rotation of the spacer 33 about the pivot 37 against the print platen 35, as is depicted in Fig. 3. This forces the print platen 35 and the recording medium 25 downward against the proper embossed character 39 on the character wheel 13. Fig. 3 shows the relative positions of the various parts during the actual printing portion of the cycle.

The print platen 35 is equipped with a return spring 41 which returns the platen 35 to its normal position after the printing cycle. A stop 43 is included in order to hold the platen in its proper normal position and prevent it from lifting beyond this normal position. The spacer 33 is also provided with a return spring 45 which lifts the spacer 33 away from the print hammer or platen 35 after the two members have contacted each other. The print platen 35 pivots about the pin 47 during its movement from normal to print positions.

After the print cycle has been completed and the operating loads removed, the lever return spring 32, the spacer return spring 45, and the platent return spring 41 operate to return their respective parts back to their initial positions. During the next revolution following a print cycle, a mechanism (not shown) moves the recording medium 25 to a blank portion for the next printing operation and the printing cycle is then ready to be repeated.

An associated means (not shown) of which several types are known in the industry, supplies synchronizing output circuit indication, in a predetermined and adjustable manner, to the associated computer through a mechanism mechanically connected to the rotating type wheel and cam member.

It will be understood by those skilled in the art that the invention has been described with reference to a particular embodiment only and that various changes and modifications may be made in the mechanism without departing from the true spirit and scope of the invention.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent of the United States is:

1. In a high speed printer for recording data, a rotating type wheel having a plurality of type characters embossed on the periphery thereof, a multilobe rotating cam member operated in mechanical relation to said type wheel, a pivotally mounted printing platen disposed between said cam member and said type wheel, and a lever having a spacer member pivotally attached to its lower end, said spacer member adapted to be inserted between said rotating cam member and said platen when said lever is actuated and operating to cause said cam member to move said platen downward with predetermined lead time against said type wheel resulting in the printing of a selected character on a recording medium interposed between said type wheel and said platen.

2. The high speed printing device defined in claim 1 wherein the pivotally attached spacer member includes a biasing means for returning it to its normal position on the lever.

3. In a high speed printer for recording data, a rotating type wheel having a plurality of type characters embossed thereon, a cam member operated in mechanical relation to the rotation of said type wheel, a pivotally mounted printing platen disposed between said cam mem ber and said type wheel and normally spaced away from said type wheel, a pivotally mounted lever adapted to swing in response to an actuating signal, and a spacer member attached to said lever and disposed in the same plane as said cam member, said spacer member being positioned between said cam member and said platen when said lever is activated causing said cam member to move said platen against said type wheel resulting in the .printing of a selected character on a recording medium interposed between said type wheel and said platen.

4. The high speed printing device defined in claim 3 wherein biasing means are included for withdrawing said pivotally mounted lever with its attached spacer after said platen has contacted and forced the recording medium against said type wheel.

5. A high speed printer for recording data flowing from an associated computing machine comprising, a constantly rotating type wheel having a plurality of selected type characters embossed thereon, a multilobe cam member driven by said type wheel through a pair of mating gears, an electromagnetic solenoid adapted to be energized by a synchronized actuating signal from the computing machine, a pivotally mounted lever arm, one end of said lever arm being attached to the plunger of said solenoid, a spacer member pivotally attached to the other end of said lever arm and disposed in the same plane as said cam member, a pivotally mounted print platen disposed near said type wheel and adapted to closely approach said type wheel, a plurality of biasing means for returning said lever arm, spacer member, and print platen to normal position, and mechanical means for interposing said spacer member between said platen and said rotating cam member causing said spacer member to force said platen to contact said rotating type Wheel through recording medium interposed therebetween to form a printed record of the selected character under the print hammer at the time of impact.

6. In a high speed printer for recording data, a rotating type wheel having a plurality of type characters at spaced intervals thereon, a cam member operated in mechanically timed relation to the rotation of said type wheel, a platen positioned above said wheel and arranged for movement toward said wheel, and a spacer member disposed in the same plane as said cam member and arranged for movement into position between said platen and said cam member in response to an actuating signal When a predetermined character approaches printing position, said cam member having a lobe thereon arranged to move said spacer and said platen toward said type wheel as the selected character thereon moves into printing position, said spacer member being arranged to apply final printing pressure when said printing character and said platen are brought into substantial engagement with a recording medium and to permit release of said spacer and said platen immediately upon further rotation of said cam member and said type wheel.

7. In a high speed printer for recording data, a rotating type wheel having a plurality of type characters at spaced intervals thereon, a rotating cam member operated in mechanical axial relationship to the rotation of said type wheel, a printing hammer positioned above said wheel between the centers of rotation of said cam member and wheel and arranged for movement toward said wheel, and a spacer member disposed in the same plane as said cam member and arranged for movement into position between said platen and said cam member in response to an actuating impulse when a predetermined type character approaches printing position, said cam member having a lobe thereon arranged to move said spacer member and said hammer toward said type wheel as a selected character moves into position and arranged to apply final printing pressure when said printing character and said hammer are brought into substantial engagement and to permit release of said spacer and said hammer immediately upon further rotation of said cam member and said type wheel as a lobe of said cam mem-- ber and print wheel character begin to move away from each other.

References Cited in the file of this patent UNITED STATES PATENTS 

